Recently, as multimedia technologies have been developed, electronic devices with various functions have been introduced, specifically portable terminals such as smart phones. It is common practice that these electronic devices have converged functions for complexly performing one or more functions.
Each of the portable terminals such as the smart phones which have been newly released to the market are capable of receiving terrestrial broadcasting, reproducing music files, photographs, or displaying moving pictures with high quality in addition to a general phone call function.
In order to perform the various additional functions, a user uses an earphone device (in general, is referred to as an earphone) with a jack plug which is inserted into a jack hole of a jack installed in an electronic device. In this earphone device, a jack plug is located at one end of a cable with a pair of ear speakers for generating sound in stereo at the other end. Also, it is common practice that a user utilizes a hands-free function during a call connection using a microphone which is installed in the cable.
The jack plug described above usually has a 3-pole or a 4-pole terminal. The 3-pole or 4-pole terminal is installed in electrically insulation. When the jack plug is inserted into the jack of the electronic device, both corresponding pins of the jack and the jack plug come in contact with and perform functions depending on a 3-pole or a 4-pole terminal.
For example, in case of a 3.5 phi 3-pole terminal, a first terminal located at the bottom of the jack plug is responsible for a SPK_L terminal, a second terminal located next to the first terminal is responsible for a SPK_R terminal, and a third terminal located next to the second terminal is responsible for a GND terminal. Each of the first to third terminals connects to respective corresponding pins of the jack electrically and performs its responsible function.
Also, in case of the 4 pole terminal, a first terminal located at the bottom of the jack plug is responsible as an SPK_L terminal, a second terminal located next to the first terminal is responsible as an SPK_R terminal, a third terminal located next to the second terminal is responsible as a GND terminal, and a fourth terminal located next to the third terminal is responsible as an MIC terminal. Each of the first to fourth terminals electrically connects to respective corresponding pins of the jack and performs its responsible function.
As described above, an jack for receiving an jack plug has a housing structure in which a plurality of pins are installed to contact corresponding pins of a jack plug. Particularly in recent years, an electric device detects an earphone by contacting the SPK_L terminal located at the bottom side of a jack plug of the earphone.
However, if conductive material such as a saline solution and water flows into a jack hole, an electronic device is short-circuited with resistance of these conductive particles. Accordingly, an electronic device recognizes as if a jack plug is inserted into a jack, and performs an erroneous operation. As a result, there is a need in the art for a reliable electronic device.